Wash sale checker
Sell at a loss, buy back within 30 days either side, and the loss is disallowed. Enter your trades — across every account — and see exactly how much of each loss survives.
Include trades from every account — a purchase in one broker washes a loss taken in another, and neither broker will report it.
Whether two securities are “substantially identical” is a judgement this cannot make for you — same-issuer stock plainly is; two providers’ S&P 500 funds are widely treated as not. Enter them under the same symbol if you consider them identical. Options, short sales and §1256 contracts have their own rules. Arithmetic, not tax advice.
The hard part of this rule is not the arithmetic, it is having every trade from every account in one place. enMoney keeps that ledger — US, Indian and Australian holdings together, imported from statements. There is no US tax pack yet. What enMoney does and doesn’t do for US filers.
The window is 61 days, not 30. Thirty days before the sale, the day itself, and thirty days after. The half everyone forgets is the first one: a purchase made before you sell triggers the rule exactly as a later one does. Buying more on the way down and then selling the original lot for the tax loss is the classic way to trip it without ever “buying back”.
The loss is usually deferred, not destroyed. A disallowed loss is added to the cost basis of the replacement shares, and the holding period of the shares you sold tacks onto them. You get the deduction when you finally sell the replacement — and the tacked holding period can make that sale long-term. For most people a wash sale is a timing problem, not a loss.
Except in an IRA. If the replacement is bought inside an IRA or Roth, the loss is disallowed and there is no taxable basis for it to attach to. Revenue Ruling 2008-5 settled this: that loss is gone permanently. Selling at a loss in a brokerage account while an automatic contribution buys the same fund in your IRA two weeks later is the most common way real money disappears under this rule.
Partial replacement is proportionate. Sell 100 shares at a loss and buy 60 back inside the window, and 60% of the loss is disallowed — the other 40% is deductible now. Buying back more than you sold does not disallow more than the loss you actually took.
Your broker will not catch all of it. A 1099-B reports wash sales within one account and one CUSIP. Sell at Fidelity and rebuy at Schwab, or rebuy in your IRA, and no statement makes the match — but the rule still applies and the adjustment is still your responsibility. That is why this tool takes trades from every account at once.
One thing it cannot decide for you: whether two securities are substantially identical. The same company's stock plainly is. Two different providers' S&P 500 index funds are widely treated as not, though the IRS has never blessed that in a ruling. Enter them under the same symbol if you consider them identical, separately if you do not.
Once you know which losses survive, the capital gains calculator works out what the rest costs.
Frequently asked questions
What is the wash sale rule?
Under §1091, if you sell a security at a loss and buy a substantially identical one within 30 days before or after the sale, the loss is disallowed for that year. The disallowed amount is added to the cost basis of the replacement shares, so the deduction is deferred until you sell those.
Is the wash sale window 30 days or 61 days?
61 days in total: the 30 days before the sale, the day of the sale, and the 30 days after. A purchase made before you sell counts just as much as one made after, which is the part most people miss.
What happens to a disallowed wash sale loss?
In a taxable account it is added to the basis of the replacement shares and the old holding period tacks on, so you claim it when you sell the replacement. It is deferred rather than lost. The exception is a replacement bought in an IRA or Roth, where the loss is permanently disallowed with no basis adjustment.
Does the wash sale rule apply across different brokerage accounts?
Yes. The rule is about you, not about an account. A loss taken at one broker is washed by a purchase at another, and by a purchase in your IRA, and by a purchase in your spouse’s account. Each broker only reports wash sales within its own account, so cross-account matches are yours to find and report.
What if I buy back fewer shares than I sold?
The disallowance is proportionate. Sell 100 at a loss and buy 60 back inside the window and 60% of the loss is disallowed; the remaining 40% is deductible this year. Buying back more than you sold does not increase the disallowance beyond the loss itself.
Can I sell an S&P 500 ETF at a loss and buy a different one?
That is the standard tax-loss harvesting move, on the view that two providers’ funds are not "substantially identical" even when they track the same index. The IRS has never ruled on it. Funds tracking different indices are safer ground; buying the identical fund back is plainly a wash.
Do wash sale rules apply to gains?
No. The rule only disallows losses. If you sell at a gain and buy straight back, the gain is taxable and nothing is deferred.